Can someone tell me how to remove a BAT in MonetDB from C code for good and for REAL? I'll probably miss something trivial, as I tried about 20 combinations of how to get rid of a previously persistent BAT, but everytime I restart my server it comes back again like a BIOS virus. Place in the source: monetdb5/src/mal/mal_authorize.mx, I want to remove an old M5system_auth_* BAT after I created a new one with converted data in the initTables function. My latest incarnation looks like this (copied and pasted from destroyImmediate): BBPlogical(b->batCacheid, buf); BBPreleaseref(b->batCacheid); BBPfix(bid); if (BBPindex(buf) == bid) { BAT *t = (BAT*)BBPgetdesc(ABS(bid)); BATmode(t, TRANSIENT); } BBPunfix(bid); said BAT looks gone in the session, but returns next time the server starts. Can I (sub)commit the removed BAT? Any hint on this strong persistence would be nice.